Selective flotation separation of ilmenite from titanaugite using mixed anionic/cationic collectors

The flotation behavior of ilmenite and titanaugite using anionic collector sodium oleate (NaOL), cationic collector dodecylamine acetate (DAA) and the mixed anionic/cationic collector (NaOL-DAA) was investigated through micro-flotation experiments, zeta potential measurements, Fourier transform infrared (FTIR) analyses, and the artificially mixed minerals flotation experiments. The results of the microflotation experiments indicate that DAA exhibits good flotation performance to both ilmenite and titanaugite at a pH > 6.0. The flotation separation of ilmenite from titanaugite can be performed using the mixed NaOL-DAA in a wide pH range of 5.0–7.0. In this pH range, the recovery of ilmenite remains constant at approximately 90%, while the recovery of titanaugite remains < 25%. The best separation result can be achieved with NaOL-DAA molar ratios of 10:1. The results of the zeta potential experiments and the FTIR analyses indicate that the adsorption of the mixed collector, NaOL-DAA, on the ilmenite surface is larger than on the titanaugite surface and that the NaOL-DAA complex might be mainly adsorbed on the ilmenite surface by chemical adsorption, apart from electrostatic adsorption. The synthetic mineral mixture micro-flotation results demonstrate that, compared to NaOL, NaOL-DAA not only increases the recovery and grade of the TiO₂ by 7.02% and 6.71%, respectively, but also decreases the reagent consumption by half.